Method for manufacturing microfibrous cellulose composite sheets and method for manufacturing microfibrous cellulose composite sheet laminate

Abstract

The present invention provides a method for easily and efficiently manufacturing microfibrous cellulose composite sheets. The present invention is a method for manufacturing microfibrous cellulose composite sheets, including a preparation process in which a polymer emulsion is mixed with an aqueous suspension including microfibrous cellulose, thereby preparing a mixed fluid, a papermaking process in which the mixed fluid is dehydrated on a porous base material through filtration, and a sheet including moisture is formed, and a drying process in which the sheet including moisture is heated and dried. In addition, the present invention is a method for manufacturing a microfibrous cellulose composite sheet laminate, in which the microfibrous cellulose sheets are thermally compressed and thus laminated as they are or after being provided with a polymer layer on at least one surface thereof.

What is claimed is: 
     
       1. A method of manufacturing microfibrous cellulose composite sheet laminate comprising:
 mixing a polymer emulsion with an aqueous suspension including microfibrous cellulose so as to manufacture a mixed fluid; 
 dehydrating the mixed fluid on a porous base material through filtration, wherein a sheet including moisture is formed; and 
 drying and heating the sheet including moisture so as to obtain a microfibrous cellulose composite sheet; 
 overlapping two or more of the microfibrous cellulose composite sheets; 
 thermally compressing the overlapped microfibrous cellulose composite sheets; and 
 providing a polymer layer on at least one surface of at least one of the microfibrous cellulose composite sheets, 
 wherein the polymer layer has the same composition as the polymer emulsion contained in the microfibrous cellulose composite sheet. 
 
     
     
       2. The method of manufacturing microfibrous cellulose composite sheet laminate according to  claim 1 ,
 wherein a solid content concentration of the mixed fluid is 3% by mass or less. 
 
     
     
       3. The method of manufacturing microfibrous cellulose composite sheet laminate according to  claim 1 ,
 wherein the polymer emulsion is formed of at least one polymer selected from the group consisting of polyurethane, polyethylene, alkyl(meth)acrylate ester copolymers, acid-denatured styrene-butadiene copolymers, and polypropylene. 
 
     
     
       4. The method of manufacturing microfibrous cellulose composite sheet laminate according to  claim 1 ,
 wherein the polymer emulsion is cationic. 
 
     
     
       5. The method of manufacturing microfibrous cellulose composite sheet laminate according to  claim 1 ,
 wherein a cellulose coagulant is mixed in the mixed fluid comprising microfibrous cellulose. 
 
     
     
       6. The method of manufacturing microfibrous cellulose composite sheet laminate according to  claim 1 ,
 wherein a fiber width of the mixing microfibrous cellulose is 2 nm to 1000 nm. 
 
     
     
       7. A method of manufacturing a microfibrous cellulose composite sheet laminate comprising:
 mixing a polymer emulsion with an aqueous suspension including microfibrous cellulose so as to manufacture a mixed fluid; 
 dehydrating the mixed fluid on a porous base material through filtration, wherein a sheet including moisture is formed; and 
 drying and heating the sheet including moisture so as to obtain a microfibrous cellulose composite sheet; 
 overlapping two or more of the microfibrous cellulose composite sheets; 
 thermally compressing the overlapped microfibrous cellulose composite sheets; and 
 providing a polymer layer on at least one surface of at least one of the microfibrous cellulose composite sheets, 
 wherein the polymer layer is obtained by applying, heating, and drying the polymer emulsion. 
 
     
     
       8. The method of manufacturing microfibrous cellulose composite sheet laminate according to  claim 7 ,
 wherein a solid content concentration of the mixed fluid is 3% by mass or less. 
 
     
     
       9. The method of manufacturing microfibrous cellulose composite sheet laminate according to  claim 7 ,
 wherein the polymer emulsion is formed of at least one polymer selected from the group consisting of polyurethane, polyethylene, alkyl(meth)acrylate ester copolymers, acid-denatured styrene-butadiene copolymers, and polypropylene. 
 
     
     
       10. The method of manufacturing microfibrous cellulose composite sheet laminate according to  claim 7 ,
 wherein the polymer emulsion is cationic. 
 
     
     
       11. The method of manufacturing microfibrous cellulose composite sheet laminate according to  claim 7 ,
 wherein a cellulose coagulant is mixed in the mixed fluid comprising microfibrous cellulose. 
 
     
     
       12. The method of manufacturing microfibrous cellulose composite sheet laminate according to  claim 7 ,
 wherein a fiber width of the mixing microfibrous cellulose is 2 nm to 1000 nm.